Early chassis mules of the next-generation Vauxhall Corsa have hit the road ahead of the supermini’s expected launch in two years’ time.

At first glance, the mule may look little more than an update of the current car, but the platform underneath is understood to be all new. The biggest tell-tale sign is how ill-fitting the rear wheels are within the bodywork.

The fifth-generation Corsa will be built on a General Motors platform rather than the underpinnings co-developed with PSA Peugeot-Citroën as part of the tie-up between the two firms. A development of the platform used for the new Vauxhall Mokka is the most likely choice.

The Astra GTC is expected to be the main inspiration for the styling of the new Corsa, particularly with the more rakish three-door model. Expect highly efficient, turbocharged, small-capacity petrol engines between 1.0 and 1.4 litres from Vauxhall’s new Small Gasoline Engine (SGE) range alongside a frugal 1.6-litre diesel from Vauxhall’s Mid-Size Diesel (MSD) family.

The Corsa had originally been tipped to be launched at the Frankfurt motor show in the autumn. But Vauxhall’s recent onslaught of new models, plus how early in the development these mules indicate the car still is, make an early 2015 launch more likely, possibly after a reveal at next year’s Paris show.